TY - CONF A1 - Müller, Werner ED - Jost, D. T1 - Eignungsgutachten für Kunststoff-Dränelemente durch die BAM KW - Kunststoff-Dränelemente KW - Eignungsgutachten KW - Deponieoberflächenabdichtung PY - 2005 SP - 213 EP - 232 PB - SKZ CY - Würzburg AN - OPUS4-11159 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Werner ED - Herrmann, R. T1 - Eignungsnachweise bei Geokunststoffen für Dämme, Deiche und Stauanlagen T2 - 2. Symposium Sicherung von Dämmen, Deichen und Stauanlagen CY - Siegen, Deutschland DA - 2006-02-09 KW - Geokunststoffe KW - Wasserbau KW - Deiche PY - 2006 VL - 2 SP - 435 EP - 440 PB - IfG CY - Siegen AN - OPUS4-14445 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Albers, K. A1 - Müller, Werner ED - Ramke, Hans-Günter ED - Witt, Karl-Josef ED - Bräcker, Wolfgang ED - Tiedt, Michael T1 - Kunststoffdichtungsbahnen als Abdichtungselement in Oberflächenabdichtungssystemen T2 - Status-Workshop "Anforderungen an Deponie-Oberflächenabdichtungssysteme" CY - Höxter, Deutschland DA - 2006-11-30 KW - Kunststoffdichtungsbahnen KW - Deponien KW - Zulassungen PY - 2007 SN - 3-9807985-5-0 VL - 06 SP - 65 EP - 85 CY - Höxter AN - OPUS4-16079 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Werner T1 - Funktionsdauer von Dränmatten als Entwässerungselemente in Oberflächenabdichtungen von Deponien und Altlasten, Erkenntnissen aus den Begutachtungen der BAM T2 - 23. Fachtagung "Die sichere Deponie", Sicherheit von Deponien und Altlasten mit Kunststoffen CY - Würzburg, Germany DA - 2007-02-01 PY - 2007 AN - OPUS4-15964 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Werner T1 - Langzeit-Scherfestigkeit von Bentonitmatten und Kunststoff-Dränelemente T2 - IV. Geokunststoff-Kolloquium der Naue Unternehmensgruppe CY - Garmisch-Partenkirchen, Germany DA - 2005-01-27 PY - 2005 AN - OPUS4-15966 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Werner T1 - Kunststoffdichtungsbahnen als Abdichtungselement in Oberflächenabdichtungen T2 - Status-Workshop, Anforderungen an Oberflächenabdichtungen CY - Höxter, Germany DA - 2006-11-30 PY - 2006 AN - OPUS4-15965 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hsuan, Y.G. A1 - Schröder, Hartmut A1 - Rowe, K. A1 - Müller, Werner A1 - Greenwood, J. A1 - Cazzuffi, D. A1 - Koerner, R.M. ED - Neil Dixon, T1 - Long-term performance and lifetime prediction of geosynthetics N2 - To properly understand and assess the long-term behaviour of geosynthetic materials it is necessary to investigate the various types of possible degradation mechanims. This includes both chemical and mechanical behaviour, and sometimes even their interactions with one another. Clearly, chemical degradation of geosynthetics depends on the polymer type. For example, polyolefins are vulnerable to oxidation; polyesters are susceptible to hydrolysis; and plasticizers can leach from polyvinyl chloride. This paper describes the concept of these three types of degradation, but focuses on the oxidation of polyolefins since the majority of the geosynthetics is made from this type of polymer. The methods used to predict the lifetime of antioxidants and service life of the geosynthetic material will be illustrated. Furthermore, the influence of temperature, pressure, and ultraviolet light on the service life are also demonstrated. Finally, the current specifications targeting the longevity of different geosynthetics are presented. Regarding mechanical degradation, the paper mainly focuses upon the creep deformation of geogrids and stress crack resistance (SCR) of polyethylene geomembranes and geopipe. The method to assess stress crack resistance is described, and the microscopic mechanisms that lead to such failure are explained. For creep evaluation, different acceleration tests are presented and their applicability with respect to the different types of polymers is illustrated. In addition, the long-term shear behaviour of geocomposites and geosynthetic clay liners is presented. T2 - 4th European Geosynthetics Conference - EuroGeo4 CY - Edinburgh, Scotland, UK DA - 2008-09-07 KW - Geosynthetic KW - Durability KW - Degradation KW - Antioxidant KW - Weathering PY - 2008 SP - 1 EP - 41 AN - OPUS4-17975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Werner A1 - Jakob, Ines A1 - Tatzky-Gerth, Renate T1 - Long-term water flow capacity of geosynthetic drains and structural stability of their drain cores KW - Geosynthetics KW - Drain elements KW - Long-term behavior KW - Water flow capacity KW - Creep behavior PY - 2008 SN - 1072-6349 VL - 15 IS - 6 SP - 437 EP - 451 PB - Telford CY - London, UK AN - OPUS4-18630 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Werner A1 - Jakob, Ines A1 - Li, C.S. A1 - Tatzky-Gerth, Renate T1 - Durability of polyolefin geosynthetic drains N2 - The German Federal Institute for Materials Research and Testing (BAM) has established a testing guideline to assess the suitability of geosynthetic or geocomposite drain (GCD) elements for final landfill cover systems. In an earlier paper the uniform procedure according to the BAM guideline for determining long-term water flow capacity was described, and the structural stability of drain cores under creep was investigated. The extrapolation of creep curves is permissible only when it can be shown, over the extrapolated period (at least 100 years), that oxidative aging does not invoke any relevant changes in the polyolefin material. This can be shown by measuring antioxidant depletion and mechanical degradation of the drain cores and filter/protection geotextiles in oven aging and water immersion tests. In this paper the results of such aging studies on three different GCD products are reported. Degradation of the tensile strength of HALS-stabilized polypropylene needle-punched nonwoven geotextiles (PP NWGTs) starts right from the beginning of the oven aging. This has to be taken into account for lifetime predictions based on residual tensile strength. The rate of oxidative degradation of NWGTs decreases significantly with increasing mass per area. Therefore the expected service life sets a limit on acceptable geotextile grammage. Antioxidant depletion in the drain cores, which are made of relatively thick PP strands or HDPE ribs, is about an order of magnitude slower than in filter and protection NWGTs, which are made of thin fibers. Service life values in excess of 100 years may be obtained for the products when the geotextiles and drain cores are properly stabilized and designed. KW - Geosynthetics KW - Geosynthetic drain elements KW - Long-term behavior KW - Oxidative degradation PY - 2009 DO - https://doi.org/10.1680/gein.2009.16.1.28 SN - 1072-6349 VL - 16 IS - 1 SP - 28 EP - 42 PB - Telford CY - London, UK AN - OPUS4-18999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Werner T1 - Dichtungsbahnen zur Abdichtung von Deponien und Altlasten T2 - 25. Fachtagung - Die sichere Deponie - Sicherung von Deponien und Altlasten mit Kunststoffen CY - Würzburg, Deutschland DA - 2009-02-26 KW - Kunststoffdichtungsbahnen KW - Deponien KW - Altlasten PY - 2009 IS - Abschnitt C SP - 1 EP - 22 CY - Würzburg AN - OPUS4-19064 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pretsch, Thorsten A1 - Müller, Werner T1 - Shape memory poly(ester urethane) with improved hydrolytic stability N2 - In two hydrolytic degradation studies the tensile (mechanical) and functional (thermo-mechanical) properties of a hydrolysis-stabilized shape memory poly(ester urethane) and its non-stabilized analog were investigated. Hydrolytic degradation was enforced by specimen immersion in de-ionized water at 80 °C. Significant differences in the fundamental shape memory parameters were monitored as function of aging time for the stabilized and non-stabilized polymer. This included the ability to recover strain (shape recoverability) and stress (stress recoverability) on heating after shape programming. Hydrolysis-related mechanical and functional changes were correlated with morphological ones, detected by differential scanning calorimetry (DSC). The shape memory poly(ester urethane), which was protected by a carbodiimide-based hydrolysis stabilizer, revealed significantly improved resistance towards hydrolysis with respect to various mechanical and shape memory parameters. KW - Shape memory polymers KW - Hydrolytic degradation KW - Stabilization KW - Thermo-mechanical properties KW - Poly(ester urethane) KW - Active polymers PY - 2010 DO - https://doi.org/10.1016/j.polymdegradstab.2009.12.020 SN - 0141-3910 SN - 1873-2321 VL - 95 IS - 5 SP - 880 EP - 888 PB - Applied Science Publ. CY - London AN - OPUS4-21270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Werner T1 - Die Zulassung von Geokunststoffen, Polymeren und Dichtungskontrollsystemen nach der neuen Deponieverordnung T2 - 26. Fachtagung "Die sichere Deponie" CY - Würzburg, Germany DA - 2010-02-18 PY - 2010 AN - OPUS4-20995 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Müller, Werner A1 - Pretsch, Thorsten T1 - Hydrolytic aging of crystallizable shape memory poly(ester urethane): Effects on the thermo-mechanical properties and visco-elastic modeling N2 - The shape memory functionality of a segmented poly(ester urethane) and its hydrolytically aged specimens has been studied by cyclic thermo-mechanical measurements with an imposed strain of 100%. The shape memory effect was triggered by a melting transition in the soft segment phase. Aging was enforced by immersion in hot de-ionized water. In the course of the immersion the tensile properties (secant moduli, stress and strain at yield and break) were impaired by hydrolysis. Advanced specimen embrittlement finally led to rupture during the first thermo-mechanical cycle. This happened after 68 days of aging at 55 °C and correspondingly after 8 days at 80 °C. The residual strain after the first cycle, which was about 25%, increased significantly with aging time. Therefore, the total strain recoverability became ever smaller: aged specimens needed conditioning by at least two cycles for a full development of shape recoverability. Likewise the recovery force decreased continuously. Despite these degradation effects, it was observed that the shape fixity and the cycle-related shape recovery of appropriately conditioned specimens (number of cycles N > 2) remained on a constant high level (at round 100% and between 90% and 100%, respectively) throughout the whole aging period. These observations are discussed within the framework of a simplified model of the behavior of crystallizable shape memory polymers. The amorphous state of the polymer is described by the equation of the linear visco-elastic solid. As for the semi-crystalline state the material is assumed to react elastically with respect to deviations from the configuration, which was frozen up under constraint conditions. The curves of the dependence of the material behavior on aging time at 55 °C match perfectly those at 80 °C when the time axis is adjusted by a factor of 8.5, from which the apparent activation energy for hydrolytic aging in the amorphous state of 82 kJ mol-1 could be deduced. KW - Shape memory polymers KW - Hydrolytic degradation KW - Thermo-mechanical properties KW - Poly(ester urethane) KW - Active polymers PY - 2010 DO - https://doi.org/10.1016/j.eurpolymj.2010.05.004 SN - 0014-3057 SN - 1873-1945 VL - 46 IS - 8 SP - 1745 EP - 1758 PB - Elsevier CY - Oxford AN - OPUS4-21819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kalbe, Ute A1 - Müller, Werner A1 - Berger, Wolfgang A1 - Eckardt, Jürgen T1 - Transport of organic contaminants within composite liner systems N2 - Composite liners (a geomembrane in intimate contact with a mineral liner) are frequently used to line landfills and contaminated sites. It is therefore very important to characterise the behaviour of these systems even under extreme conditions. An investigation was undertaken to determine the influence of a mixture of concentrated organic contaminants on composite liner materials taken from test cells that had been dismantled after a 12-year permeation test. The organic hydrocarbons had permeated the HDPE-geomembrane and had then migrated or had been adsorbed within the mineral liners, depending on their properties. The obtained concentration profiles of the contaminant mixture components indicate that the various mineral layer materials have selective retardation abilities which correspond to the different parameters of the organic compounds as well as of the mineral layer. In addition, contaminant transport in the composite liners tested was modelled and the results of the model analysis compared with measurement data. An example (acetone) illustrates the calculated spatial and temporal contaminant concentration. The composite liners investigated exhibit a very good sealing capacity against the concentrated organic contaminants used. KW - Composite liner system KW - Transport modelling KW - Contaminants PY - 2002 DO - https://doi.org/10.1016/S0169-1317(01)00093-X SN - 0169-1317 SN - 1872-9053 VL - 21 IS - 1-2 SP - 67 EP - 76 PB - Elsevier CY - Amsterdam AN - OPUS4-1353 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Thies, Martina A1 - Gerloff, Constantin A1 - Müller, Werner A1 - Seeger, Stefan ED - Koerner, R. ED - Gartung, E. ED - Zanzinger, H. T1 - Long-term shear testing of geosynthetic clay liners T2 - International Symposium [on Clay Geosynthetic Barriers] IS CY - Nuremberg, Germany DA - 2002-04-16 PY - 2002 SN - 90-5809-380-8 SP - 97 EP - 104 PB - Balkema CY - Lisse AN - OPUS4-1362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -